Process and apparatus for treatment of incinerator bottom ash and fly ash

ABSTRACT

A method for treatment of ash from incineration plants includes: collecting ash from an incinerator; feeding the collected ash and additional feed material to a gasification/vitrification reactor; vitrifying the ash and additional feed material in the gasification/vitrification reactor, to form a slag of molten material; allowing the slag to flow from the gasification/vitrification reactor and solidify outside the gasification/vitrification reactor; gasifying volatile components in the ash and the additional feed material; combusting syngas generated in the gasification/vitrification reactor in a secondary combustion zone in the gasification/vitrification reactor; and supplying products of the syngas combustion to the incinerator to augment the thermal environments of the incinerator. An apparatus used to practice the method is also provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.13/445,255, filed Apr. 12, 2012, entitled “Process and Apparatus forTreatment of Incinerator Bottom Ash and Fly Ash”, which claims thebenefit of U.S. Provisional Patent Application Ser. No. 61/517,064,filed Apr. 13, 2011, entitled titled “Process and Apparatus forTreatment of Incinerator Bottom Ash and Fly Ash”, both of which areincorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to methods and apparatus for treating ash productsof incineration for safe, economical disposal.

BACKGROUND

Typical fossil fuel power plants, and other incineration apparatus, suchas waste incinerators, produce large amounts of bottom ash, left asresidue in a combustor from the fuel combustion, and fly ash, exitingwith gaseous combustion products in (flue gas) stack emissions. The ashproducts may contain substantial amounts of toxic matter, such aselemental metals, metal oxides, sulfur, and chlorine, consideredhazardous to the environment. The ash composition often results inrestrictions on the disposal of the ash and may require substantialexpense in collecting and hauling the ash to a hazardous waste sitewhich may be inconveniently located and have considerable deposit fees,and such a site itself remains an environmental hazard,

Suggestions have been made for processing ash by various treatments to aform intended to result in a reduced hazard with less expense ofdisposition. These have not been adopted to a large extent and thereremains a need and desire for more effective and efficient treatment.

SUMMARY

In a first aspect, a method for treatment of ash from incinerationplants includes: collecting ash from an incinerator; feeding thecollected ash to a gasification/vitrification reactor; vitrifying theash in the gasification/vitrification reactor, to form a slag of moltenmaterial; allowing the slag to flow from the gasification/vitrificationreactor and solidify outside the gasification/vitrification reactor;gasifying volatile components in the ash; combusting syngas generated inthe gasification/vitrification reactor in a secondary combustion zone inthe gasification/vitrification reactor; and supplying products of thesyngas combustion to the incinerator to augment the thermal environmentsof the incinerator. In another aspect, an apparatus includes anincinerator, a gasification/vitrification reactor, a first feed passagefor transporting bottom ash from a bottom of the incinerator to thegasification/vitrification reactor, an incinerator exhaust gas fly ashrecovery system, a second feed passage for transporting fly ashcollected by the recovery system to the gasification/vitrificationreactor, and a third passage for routing syngas generated in thegasification/vitrification reactor back to the incinerator.

In another aspect, an apparatus includes: an incinerator; agasification/vitrification reactor; a first feed passage fortransporting bottom ash from a bottom of the incinerator to thegasification/vitrification reactor; an interface connecting a secondarycombustion zone in the gasification/vitrification reactor to theincinerator allowing products of syngas combustion produced in thegasification/vitrification reactor to flow directly to the incinerator;and an air inlet in the secondary combustion zone in thegasification/vitrification reactor.

In another aspect, an apparatus includes: an incinerator; agasification/vitrification reactor; a first feed passage fortransporting bottom ash from a bottom of the incinerator to thegasification/vitrification reactor; an interface connecting a secondarycombustion zone in the gasification/vitrification reactor to theincinerator; and a burner or an igniter for igniting the syngas in thesecondary combustion zone; wherein the secondary combustion zone isconfigured to allow products of syngas combustion produced in thegasification/vitrification reactor to pass from the secondary combustionzone into the incinerator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an example ash treatment system.

FIG. 2 is a block diagram of another example ash treatment system.

FIG. 3 is a schematic illustration of some parts of an example ashtreatment system.

FIG. 4 is a schematic illustration of some parts of another example ashtreatment system.

DETAILED DESCRIPTION

An apparatus and process is described in which either, or both, bottomash and fly ash can be treated for disposition. In various embodiments,the process can include some or all of the steps of, for example,collecting fly ash from incinerator exhaust and bottom ash from anincinerator, feeding the collected fly ash and bottom ash to agasification/vitrification reactor (GVR), optionally supplying anadditional feed material other than the ash to the GVR, which feedmaterial may be any material suitable for gasification such as municipalsolid waste (MSW), refuse-derived fuel (RDF), biomass, coal, hazardouswaste, medical waste, liquid waste streams of coal or other carbonaceousproducts, or a combination of any such materials, vitrifying the ash,and any other inert constituents in the feed material, in the GVR, toform a slag of molten material that includes a substantial amount (e.g.,up to about 90% or more) of the hazardous material from the feedmaterial, allowing the slag to flow from the GVR and solidify outsidethe GVR ready for safe disposition without environmental concerns,gasifying volatile components in the fly ash, bottom ash, and additionalfeed material, and routing any syngas generated in the GVR back to theincinerator where it can be combusted in order to augment the thermalenvironment of the incinerator.

Apparatus for performing the process may take a variety of forms amongwhich are, as parts of an overall system in combination, an incinerator,a gasification/vitrification reactor (GVR), for example, a plasmagasification/vitrification reactor (PGVR), a first feed conduit fortransporting bottom ash from the bottom of the incinerator to the GVR,an incinerator exhaust gas fly ash recovery system that may include oneor more of a heat recovery steam generator (or boiler or heatexchanger), a scrubber, and a bag filter between the incinerator and anemission stack, and a second feed conduit for transporting fly ashcollected by the recovery system to the GVR. The GVR can include a slagtap hole and an external slag receptacle can be provided forsolidification of the slag.

Numerous variations in the process or apparatus can be included. Forexample, the bottom ash and the fly ash may be fed together, orseparately, to the GVR and the ash may be fed with other feed material,or not. If a plasma gasification/vitrification reactor (PGVR) is used,the ash, and other material if used, may be fed through a charge door(or feed chute) above a carbonaceous bed of the PGVR or through a tuyereinto the carbonaceous bed, either with or separate from a plasma torchplume. One apparatus that includes the injection of particulate materialwith a plasma torch plume is shown in U.S. Pat. No. 4,761,793, by Dighe,for a “Plasma Fired Feed Nozzle”, which is hereby incorporated byreference.

Embodiments include those in which gaseous products of the gasifier aresupplied as a syngas to the incinerator and/or are supplied to a heatexchanger which may be interconnected with a heat recovery steamgenerator of the incinerator exhaust gas system.

Additional optional variations in the process and apparatus aredescribed below, all of which are examples of the suitable techniquesfor ash treatment.

It is believed the described subject matter offers opportunities forimproved, economical results in ash treatment. Among favorable aspectsattainable are not only easier disposition of metal and other toxicconstituents of ash because of a change of form (or vitrification), tosolids from which those constituents are not likely to leach out of, butalso the destruction of toxic materials such as dioxin and furan.

Referring to FIG. 1, a system is shown that includes an incinerator 10and a gasification/vitrification reactor (GVR) 12. The incinerator 10has a bottom ash outlet 13. A feed loop or passage in the form of aconduit 14 from the outlet 13 of incinerator 10 to the GVR 12 isprovided for supplying bottom ash from the incinerator to the GVR.

The incinerator 10 includes an exhaust gas outlet 15 that is connectedby a passage in the form of a conduit 16 to a fly ash recovery system 18which, in this example, includes, in series, a heat recovery steamgenerator (or boiler) 20, a scrubber 22, and a bag filter 24 from eachof which some fly ash is recovered from outlets 20 a, 22 a, and 24 arespectively, of those individual components.

The steam generator 20 is shown with a supply of boiler feed water (BFW)and an outlet of steam (e.g., to be supplied to a turbine for powergeneration).

Fly ash, and incidental other matter, recovered from the outlets 20 a,22 a, and 24 a is combined together in a passage in the form of aconduit 26 that is connected to a passage in the form of a conduit 28for supplying fly ash to the GVR 12. Some of the constituents collectedfrom the outlets 20 a, 22 a, and 24 a may exit the conduit 26 by a slipstream conduit 30 for further treatment and disposal outside thedescribed system. It is usually intended to design and operate thesystem to maximize the amount of fly ash and related material from theconduit 26 fed to the GVR 12 via the conduit 28.

Recycling ash to the gasifier may still cause some volatile metals to goback up into the incinerator. Since not all metals can be removed in theslag, there may be a build-up of certain metals (e.g., mercury, lead,zinc and other) in the ash stream. A slip stream can be used to balanceout such metals in the ash stream. The slip stream can have a muchsmaller mass than the original ash stream.

Some gaseous and other material from the incinerator exhaust 15 may passthrough the fly ash recovery system 18 without being collected and suchgaseous and other material can be exhausted as stack gas at an outlet32. The scrubber 22 and bag filter 24, and/or possible other equipment,can provide sufficient collecting and cleaning of the emissions so thestack gas through outlet 32 is safe to discharge to the atmosphere. Itis not necessary to discharge all carbon dioxide; any products ofcombustion can be usefully recycled back to the GVR 12 if desired.

The action of the GVR 12 results in significant destruction of toxicconstituents of the fly ash streams from conduits 14 and 28, such asdioxin and furan, in addition to slag formation. Slag can be let out ofthe gasifier 12 through a bottom tap hole 12 a when it is in a molten(or vitreous) form, and directed by a conduit 34 to a receptacle (notshown) for solidification. The solidified stag would contain majoramounts of metal and other undesirable elements of the fly ash (as wellas from the other feed material if used) treated in the GVR. Any slagformation process described herein may include the addition of fluxingagents to the GVR.

In addition, the example of FIG. 1 shows an upper outlet 12 b of the GVR10 for gaseous products of the GVR that can be fed through a conduit 36as a syngas for combustion in the incinerator 10.

Tables 1 and 2 have data representative of the performance of the systemshown in FIG. 1.

TABLE 1 Startup Initial Condition 2 4 5 1 Fly ash 3 Gasifier Fly ashslip Bottom ash Recirculation Slag Carryover stream Component kg/daykg/day kg/day kg/day kg/day S 132.50 136.20 94.66 174.04 0.00 Cl 152.50429.00 20.12 561.38 0.00 Si 3725.0 678.00 4400.80 2.20 0.00 Al 1917.50473.40 2387.55 3.35 0.00 Ca 4050.00 942.00 4598.63 393.37 0.00 Fe 857.5049.80 904.49 2.81 0.00 Na 477.50 224.40 608.90 93.00 0.00 K 205.00184.80 316.95 72.85 0.00 Mg 582.50 157.20 733.41 6.29 0.00 P 170.0028.80 198.24 0.56 0.00 B 2.75 0.90 3.20 0.45 0.00 Mn 15.50 1.92 17.370.05 0.00 Pb 18.50 5.46 1.23 22.73 0.00 Cd 0.50 0.36 0.01 0.85 0.00 As0.07 0.04 0.00 0.11 0.00 Hg 0.02 0.01 0.00 0.03 0.00 Zn 94.00 51.8435.61 110.23 0.00 Cu 51.25 15.96 59.34 7.87 0.00 Cr 8.50 1.74 10.24 0.000.00 Se 0.01 0.00 0.01 0.00 0.00 Sn 215.00 13.20 215.99 12.21 0.00Oxygen in 12323.90 2604.96 13400.15 1528.72 0.00 oxides Total 25000.006000.00 28006.91 2993.09 0.00 PCCD/PCDF 160 320 0.012 1 (dixoins) (ng/g)TEQ (ng/g) 1.5 3.7 0.0005 0.0064

TABLE 2 Startup Initial Condition 2 5 1 Fly ash 4 Fly Bottom Recir- 3Gasifier ash slip ash culation Slag Carryover stream Component kg/daykg/day kg/day kg/day kg/day S 132.50 233.21 128.84 236.87 139.86 Cl152.50 908.41 36.71 1024.21 544.79 Si 3725.0 425.12 4148.05 2.08 254.95Al 1917.50 297.87 2212.26 3.10 178.64 Ca 4050.00 829.20 4494.72 384.48497.28 Fe 857.50 32.86 887.60 2.76 19.70 Na 477.50 196.06 584.32 89.25117.58 K 205.00 157.92 295.09 67.83 94.71 Mg 582.50 101.90 678.59 5.8261.11 P 170.00 18.33 187.81 0.53 10.99 B 2.75 0.84 3.15 0.44 0.50 Mn15.50 1.23 16.68 0.05 0.74 Pb 18.50 35.34 2.77 51.07 21.19 Cd 0.50 1.400.02 1.88 0.84 As 0.07 0.18 0.00 0.25 0.11 Hg 0.02 0.06 0.00 0.07 0.03Zn 94.00 145.61 58.51 181.10 87.33 Cu 51.25 14.81 58.33 7.74 8.88 Cr8.50 1.09 9.59 0.00 0.65 Se 0.01 0.00 0.01 0.00 0.00 Sn 215.00 15.98218.62 12.36 9.58 Oxygen in 12323.90 2582.57 13380.05 1526.42 1548.82oxides Total 25000.00 5999.99 27401.70 3598.29 3598.30 PCCD/PCDF 160~200 0.012 1 ~200 (dixoins) (ng/g) TEQ (ng/g) 1.5 ~2.3 0.0005 0.0064~2.3

The tables show quantities of components at various locations in thesystem. Column numbers of the tables correspond to the single digits inFIG. 1. Column 1 refers to bottom ash from the incinerator 10 thatpasses through the conduit 14; column 2 refers to recirculated fly ashthat passes through the conduit 28; column 3 refers to slag extractedout of the GVR through conduit 34; column 4 refers to GVR carryover(e.g., syngas) that passes through conduit 36; and column 5 refers tothe slip stream from conduit 30. Table 1 shows the quantities underinitial start-up conditions and Table 2 shows the quantities after theoperation has reached an equilibrium condition. The quantities arelisted in kilograms per day. Among the significant facts indicated bythis data are that of a total ash output with metals and their oxides,plus S and Cl, of 25,000 kg/day in bottom ash and 65,000 kg/day in flyash (i.e., a total of about 31,000 kg/day), at equilibrium the slagcontains about 27,400 kg/day (or about 88%) of such materials in thisexample, leaving only a small amount in the slip stream to be otherwisedisposed of.

Tables 1 and 2 also show that the dioxin and toxic equivalent (TEQ)content of the slip stream in column 5 is reduced from the quantities inthe total ash quantities.

Some incinerators operate inefficiently, and leave a large amount ofcarbon in the bottom ash. By recycling the bottom ash and returning thegas produced in the gasifier over the grate of the incinerator, theincinerator temperature can be increased, thereby improving the carbonconsumption within the incinerator itself.

FIG. 2 illustrates another example system. Like parts of the system ofFIG. 2 are assigned the same reference numbers as in FIG. 1. Among thevarious differences from the system of FIG. 1 are: instead of supplyinga syngas from a GVR 12 back to the incinerator 10, in FIG. 2 the ash isprocessed in a vitrification reactor (VR) 112. The energy used tovitrify the inert constituents may come from a fuel, from a waste streamhaving suitable energy content, and/or through the application of aplasma such as is used in a plasma vitrification reactor. This type ofreactor can be operated under oxidizing conditions such that the gaseousoutput is flue gas. The flue gas output from an upper exit 112 b passesto another ash recovery system 118 having a heat exchanger 120, ascrubber 122, and a bag filter 124 with ash, and possible othermaterial, collected from the respective outlets 120 a, 122 a, and 124 agoing to a conduit 130 for withdrawal from the system and furthertreatment elsewhere. Gaseous effluent from the system 118 passes througha conduit 132 to a stack, along with gases in conduit 32 from the system18. The heat exchanger 120 of the recovery system 118 has an inlet forboiler feed water (BFW) that is preheated by the VR emissions and thensupplied to the heat recovery steam generator 20 of the recovery system18.

In the system of FIG. 2, the reactor is used as a vitrifier that canfully combust any material within the vessel while slagging any ashcomponent to the extent possible. Rather than recycling hot gas back tothe incinerator, heat is recovered in a heat exchanger and used to heatboiler feed water that is used by the heat recovery steam generator 20.Then the output from the vitrifier is cleaned and exhausted. The systemof FIG. 2 allows for customization of the clean-up equipment for thevitrifier exhaust gas flow (e.g., smaller size) and the specificmetals/contaminants for the vitrifier exhaust gas stream. Overall, thismay provide a better clean-up system, possibly with a lower emissionsprofile. In the system of FIG. 1, all gas from the gasifier is returnedto the incinerator.

The system of FIG. 2 also differs from the system of FIG. 1 in that thefly ash collected by the fly ash recovery system 18 is supplied by aconduit 27 that is coupled to conduit 14, which has bottom ash from theincinerator 10, and the fly ash and bottom ash are supplied together tothe VR 112.

Table 3 shows a stream summary showing an even greater diminishment inash requiring additional treatment (hazardous waste disposal). Themetals and oxides plus S and Cl, in slag from the VR, shown in column 3,amount of about 90% of those constituents in the ash as shown in columns1 and 2 with correspondingly less ash for other treatment as shown incolumn 4. Additionally, the FIG. 2 system provides significantly reducedoutput amounts of dioxins and TEQ requiring other treatment. Of course,systems and processes as described herein may be usefully applied evenwithout such results.

TABLE 3 Stream Summary 4 1 2 3 Ash For Bottom ash Fly ash Slag TreatmentComponent kg/day kg/day kg/day kg/day S 132.50 136.20 94.65 174.05 Cl152.50 429.00 20.12 561.38 Si 3725.0 678.00 4400.67 2.33 Al 1917.00473.40 2387.63 3.27 Ca 4050.00 942.00 4598.45 393.55 Fe 857.50 49.80904.45 2.85 Na 477.50 224.40 608.87 93.03 K 205.00 184.80 316.93 72.87Mg 582.50 157.20 733.38 6.32 P 170.00 28.80 198.24 0.56 B 2.75 0.90 3.200.45 Mn 15.50 1.92 17.37 0.05 Pb 18.50 5.46 1.23 22.73 Cd 0.50 0.36 0.010.85 As 0.07 0.04 0.00 0.11 Hg 0.02 0.01 0.00 0.03 Zn 94.00 51.84 35.61110.23 Cu 51.25 15.96 59.34 7.87 Cr 8.50 1.74 10.24 0.00 Se 0.01 0.000.01 0.00 Sn 215.00 13.20 222.84 5.36 Oxygen in oxides 12323.90 2604.9613400.57 1528.30 Total 25000.00 6000.00 28013.82 2986.18 PCCD/PCDF 160320 0.012 1 (dixoins) (ng/g) TEQ (ng/g) 1.5 3.7 0.0005 0.0064

Various features of the system of FIG. 2 may be applied individually toa system such as that of FIG. 1, as well as together in combination asshown in FIG. 2.

The scrubbers 22 and 122 of the above described systems may be arrangedso their inputs, from a source (not shown) in addition to the components20 and 120, respectively, include amounts of scrubbing agents such aslime and activated carbon.

Additional aspects of the systems that may be varied include: variationsin reactor inputs of external feed materials, whether or not with theuse of plasma torches; or variations in the amount of input air oroxygen to the reactor (e.g., to get more or less complete stoichiometriccombustion), including: for a system such as that of FIG. 1 intended toproduce a syngas for the incinerator 10, sub-stoichiometric amounts ofair, oxygen, or both, that may be supplied (or allowed in) to thereactor 12, while more complete, stoichiometric, quantities can bepresent in the reactor of a system such as that of FIG. 2 for producingflue gas. In other embodiments, air, oxygen, or both, can be supplied tothe vitrification reactor, wherein the amount of oxygen exceeds astoichiometric amount.

In another embodiment, the system may be arranged with optionallyoperated conduits and valves so the same system can be operated ineither a syngas mode or a flue gas mode when desired.

In addition to, or instead of, supplying syngas output from a GVR to anincinerator, as shown in FIG. 1, the syngas may have differentdownstream applications, e.g., for producing any one or more of heat,steam, power, and liquid fuels.

For optional operation in a flue gas mode, an additional burner may beprovided in the top (e.g., the upper volume) of the reactor, forcombusting syngas produced in the lower portion of the reactor, whileadding air or oxygen, or both, to the syngas.

Any such production of flue gas from syngas may also be performed bysending the syngas to a combustor external to the GVR.

The ash recovery system 118 of FIG. 2 is an example of a dedicated gascleanup system which may be used for either flue gas or syngas cleanupto remove fly ash, unreacted carbon, volatile metals, sulfur andchlorine species that may be present.

Any products of a cleanup system, such as system 118, may be introducedback into any incinerator (or GVR) in addition to, or instead of,released directly as stack gas to the atmosphere.

The system of FIG. 2 integrates the steam system from a boiler/heatexchanger on the vitrification reactor side with the steam system of theincinerator. The vitrification reactor steam system recovers someadditional energy that would not otherwise be recovered. Carbon from thebottom ash and fly ash is combusted in the vitrification reactors andthe energy is recovered as heat. This heat can be converted to steam andcombined with the steam system of the incinerator for power production.

It will be apparent that further modifications, and combinations ofmodifications, of the described systems may be practiced as well. Forexample, in any system of either FIG. 1 or 2, and the mentionedvariations, the reactor can be directly attached to the incinerator orcan be free standing and connected with the incinerator by any neededconduits (which may be any form of passageways, e.g., in the form ofmetal ductwork or piping or masonry).

FIG. 3 shows a generalized schematic of an example system in which anincinerator 210 is combined, or integrated, with a reactor 212 that isclose by, with a feed chute 213 for bottom ash from the incineratorhaving a feed leg 214 directly coupled to the reactor. In oneembodiment, the illustrated ash feed chute apparatus 213 can include aninternal diverter spool piece (not shown) for optional use, such as todivert ash from the reactor 212 when the reactor is shut down. FIG. 3additionally shows a syngas exit 212 b from the reactor 212 that has adirect connection with structure of the incinerator 210 at an interface236.

The apparatus shown in FIG. 3 can be used for treatment in the reactor212 of bottom ash from the incinerator 210 (normally of a much largerquantity than the fly ash likely to be produced by the incinerator). Theapparatus of FIG. 3 could be further modified for fly ash treatment,such as according to FIG. 1 or 2. FIG. 4 shows a modification of FIG. 3with a feed port 228 for introducing fly ash into the reactor 212. Usingthe example of FIGS. 3 and 4, certain conduits of FIGS. 1 and 2 can bereplaced with other types of passages for delivering ash of additionalmaterials to the reactor.

Some of the features of the apparatus of FIG. 3 that are present (or areoptionally provided) are that air (oxygen) for the incinerator 210 andthe reactor 212, facilitated by their close proximity, may come from thesame air blower source (not shown). That would include air forgasification in the GVR 212 and also any air for other purposes such asGVR syngas combustion, if desired, and plasma torch gas or shroud gas,if used.

FIG. 3 shows the example reactor 212 that includes an inlet 238 into itsupper region for syngas combustion air. Such a location can also beprovided, optionally, with a burner (or igniter) for the syngas, to beused when desired. An upper part of the reactor 212 is referred to as asyngas secondary combustion zone in this example.

FIG. 3 shows an example reactor 212 that is a plasma GVR with plasmatorches 240 for directing a plasma plume into a bottom section of theGVR (which would normally have a carbonaceous bed within it).

The reactor 212 also has an additional feed material inlet (nozzle ortuyere) 242 for any feed material in addition to the bottom ash from theincinerator 210. The additional feed material may be among any of thosepreviously mentioned, or otherwise desired to be provided, includingsuch things as medical waste, coke (or other carbonaceous) additions,and various mixtures of feed materials.

At the bottom of the reactor 212 is a tap hole 212 a for slag outputthat flows through a conduit 234 to some receptacle. While a variety ofreactor types may be used in the described systems, ones that stand outare plasma GVRs to gasify and/or vitrify the ash. Of particular interestare plasma GVRs of the type having a stationary bed of carbonaceousmaterial (e.g., metallurgical coke or other carbon) in a bottom sectionof a vertical reactor structure with tuyeres for plasma torches and forpossible inlet air, other gases and/or particulate solids. Particularexamples of suitable plasma GVRs, and also the providing of carbonaceousbeds that may include substantial amounts of carbon not from fossilfuels, can be found in U.S. Patent Application Publication No.2010/0199557, Aug. 12, 2010, by Dighe et al., entitled “PlasmaGasification Reactor”; U.S. Patent Application Publication No.2012/00061618, Mar. 15, 2012, by Santoianni et al.; and U.S. patentapplication Ser. No. 13/199,813, filed Sep. 9, 2011, by Gorodetsky etal., all of which are incorporated by reference herein for theirdescriptions of plasma GVRs, gasification systems, and their operation.

Additional PGVRs and their various uses are described in, for example,U.S. Pat. No. 7,632,394 by Dighe et al., issued Dec. 15, 2009, entitled“System and Process for Upgrading Heavy Hydrocarbons”; and U.S. PatentApplication Publication No. 2009/0307974 by Dighe et al., entitled“System and Process for Reduction of Greenhouse Gas and Conversion ofBiomass”; which are incorporated by reference herein for theirdescriptions of PGVRs and methods practiced with them.

While various embodiments of the invention have been described herein,it should be apparent, however, that various modifications, alterationsand adaptations to those embodiments may occur to persons skilled in theart with the attainment of some or all of the advantages of the presentinvention. The disclosed embodiments are therefore intended to includeall such modifications, alterations and adaptations without departingfrom the scope of the present invention as set forth in the appendedclaims.

What is claimed is:
 1. A method for treatment of ash from incinerationplants, the method comprising: collecting ash from an incinerator;feeding the collected ash to a gasification/vitrification reactor;vitrifying the ash in the gasification/vitrification reactor, to form aslag of molten material; allowing the slag to flow from thegasification/vitrification reactor and solidify outside thegasification/vitrification reactor; gasifying volatile components in theash; combusting syngas generated in the gasification/vitrificationreactor in a secondary combustion zone in the gasification/vitrificationreactor; and supplying products of the syngas combustion to theincinerator to augment the thermal environments of the incinerator. 2.The method of claim 1, further comprising: feeding additional feedmaterial to the gasification/vitrification reactor, wherein theadditional feed material comprises at least one of municipal solid waste(MSW), RDF, biomass, coal, hazardous waste, medical waste, liquid wastestreams of coal or other carbonaceous products, or a combinationthereof.
 3. The method of claim 1, wherein the ash comprises: bottom ashand the fly ash fed into the gasification/vitrification reactor togetheror separately.
 4. The method of claim 1, wherein the ash is fed througha charge door or feed chute above a carbonaceous bed of thegasification/vitrification reactor.
 5. The method of claim 1, whereinthe ash is fed through a tuyere into a carbonaceous bed of thegasification/vitrification reactor.
 6. The method of claim 1, whereinair or oxygen is fed into the secondary combustion zone in thegasification/vitrification reactor.
 7. The method of claim 1, whereinthe molten slag includes hazardous material from the additional feedmaterial.
 8. The method of claim 7, wherein the molten slag includes upto about 90% of the hazardous material from the additional feedmaterial.
 9. The method of claim 1, further comprising: supplyingsub-stoichiometric amounts of air, oxygen, or both, to thegasification/vitrification reactor.
 10. The method of claim 1, whereinthe products of syngas combustion flow into the incinerator in adirection opposite to the movement of the ash.
 11. An apparatuscomprising: an incinerator; a gasification/vitrification reactor; afirst feed passage for transporting bottom ash from a bottom of theincinerator to the gasification/vitrification reactor; an interfaceconnecting a secondary combustion zone in the gasification/vitrificationreactor to the incinerator; and a burner or an igniter for ignitingsyngas in the secondary combustion zone; wherein the secondarycombustion zone is configured to allow products of syngas combustionproduced in the gasification/vitrification reactor to pass from thesecondary combustion zone into the incinerator.
 12. The apparatus ofclaim 11, further comprising: an air inlet in a secondary combustionzone of the gasification/vitrification reactor to the incinerator. 13.The apparatus of claim 11, further comprising: an incinerator exhaustgas fly ash recovery system; and a second feed passage for transportingfly ash collected by the recovery system to thegasification/vitrification reactor.
 14. The apparatus of claim 13,wherein the incinerator exhaust gas fly ash recovery system comprisesone or more of: a heat recovery steam generator; a boiler; a heatexchanger; a scrubber; and a bag filter, between the incinerator and anemission stack.